Whenever I notice veterinarians widely prescribing a new drug … I like to look at the history of that pharmaceutical. History can tell us a lot … so can the money trail. I also look up the scientific research behind the drug. I read those double-blind placebo-controlled studies. The ones that Big Pharma and conventional vets use to bully the alternative medicine community.
About 7 or 8 years ago I began hearing about a lot of dogs with arthritis, neuropathic pain and chronic pain. And these dogs with obvious signs of pain were taking gabapentin and Tramadol instead of anti-inflammatories or a non-steroidal anti-inflammatory drug (NSAID).
Many of the owners were calling me. Their dogs weren’t reacting well to the medications … and they were still in considerable pain. And an 80 lb Lab who can’t get up and walk is a problem. It can lead to life and death decisions.
Here are some of the things dog owners noted.
Common Side Effects Of Gabapentin In Dogs
- Diarrhea, black tarry stools and vomiting
- Change in behavior, aggressiveness
- Low energy, drooling, sedation and mental distress
- Rolling eye movement
- Ataxia, clumsiness, loss of balance, unsteady gait, loss of coordination
- Loss of appetite
- Gastrointestinal distress
- Increased anxiety or agitation (from a medication prescribed to treat both!)
- Fluid retention in limbs and extremities
And even more serious are allergic reactions that include:
- Difficulty breathing
- Swelling of the lips, tongue or face
So what was this new drug for dogs called gabapentin? And why was it suddenly flooding the veterinary market for chronic conditions?
History Of Gabapentin
Gabapentin was first developed in 1975 as an anti-seizure medication. In 1993, the FDA approved it to treat epilepsy for humans. And then in 2002, the FDA approved it to treat postherpetic neuralgia (shingles). Gabapentin is best known under Pfizer’s brand name, Neurontin. And it became one of Pfizer’s best-selling drugs in human medicine. But within a few years, Pfizer (then Warner-Lambert) was in litigation.
That’s because they had violated federal racketeering law by improperly promoting the drug. They were illegally marketing gabapentin … for at least a dozen off-label uses that the FDA hadn’t approved. And off-label prescriptions accounting for a whopping 90% of Neurontin sales.
Pfizer settled the off-label case in 2004. They paid criminal charges and civil liabilities totaling $430 million. It was one of the largest pharmaceutical settlements in history. And then, in 2009, pregabalin, a gabapentin derivative called Lyrica … was part of a massive $2.3 billion dollar settlement against Pfizer. Not only was the drug used off-label … it was causing many concerns in the medical field. It induced pancreatic cancer in rats. In humans, there were reports of:
- Myoclonus (involuntary muscle jerking)
- Suicidal thoughts
- Withdrawal syndrome (confusion, agitation, upset stomach, delirium)
Check out the huge list of oral gabapentin side effects on the Mayo Clinic’s website. And yet gabapentin is a human medication that got the nod from veterinarians.
Gabapentin In Veterinary Medicine
Most dogs are prescribed gabapentin to treat chronic pain associated with arthritis and cancer as well as neural and post-operative pain. It’s often prescribed alongside NSAIDs or opiates. It’s thought to amplify their effect on pain management despite potential side effects.
But here’s why it’s not such a good medication to be giving your dog.
2008 was one of the earliest references I could find to Gabapentin in veterinary medicine. There was a short article on Veterinary Information Network (VIN), revised in 2017. That’s right. Despite the 2004 and 2009 settlements against Pfizer … in 2008 the drug showed up in the veterinary community being prescribed for pain, anxiety in dogs and seizures.
This is what the recent Plumb’s Veterinary Drugs had to say:
- Caution in renal failure or insufficiency
- Extra-label use in seizures in dogs; “evidence to support use is relatively weak”
- Extra-label use as an adjunctive analgesic: “Evidence to support use strengthens in recent years … may be effective in some dogs, for chronic pain in dogs with a neuropathic component”
Note the cautious language: “may be,” “some dogs,” “extra-label.” There’s not much confidence in its effectiveness. Other veterinary articles … not research studies … stated some interesting tidbits:
Gabapentin can cause deficiencies in calcium as it works on the calcium channels … not on the neurotransmitter GABA (it was designed to mimic the chemical structure of gamma-aminobutyric acid). It can also cause deficiencies in vitamin D, vitamin B1, and folate. Ironically, all these nutrients help with nerve repair.
Cautions With Gabapentin For Dogs
There are several reasons to be very wary of giving gabapentin to your dog.
- Use of gabapentin in dogs is not FDA-approved … but vets still frequently prescribe it to manage various types of pain … including pain from intervertebral disc disease, as well as other conditions like anxiety, idiopathic epilepsy and seizures in dogs.
- The kidneys and liver are needed for the metabolism of gabapentin so it should be avoided by dogs with liver or kidney disease.
- Pregnant or nursing dogs, or dogs taking antacids, hydrocodone or morphine should not take it to avoid drug interactions.
- Most dogs develop tolerance over time when trying to get chronic pain relief … so they need higher doses of gabapentin. The risk of side effects increases along with the dose of gabapentin, of course. This makes it easy to overdose and increase side effects … and the cycle continues.
Research About Gabapentin For Dogs
There have been zero controlled research studies on gabapentin to treat chronic pain. And case reports show mixed results.
I found no double-blind placebo-controlled research studies on gabapentin for dogs. That means there’s no information to support its use in treating chronic pain. If you find one please forward it to me!
A 2018 review found that gabapentin was of no benefit in sciatica or lower back pain in humans.
Another study in 2009 found gabapentin influences a receptor that helps create new synapses in the brain. Gabapentin can block a specific receptor that’s responsible for making new neuronal connections. Connections that help grow, develop and repair the brain. This means that gabapentin can actually inhibit new neural connections from forming.
What Happens When Gabapentin Is Prescribed For Dogs
I have never prescribed gabapentin myself, nor would I.
The dogs I see on gabapentin come to me already taking it. And I find other options to replace gabapentin quickly. Why? Because of what I’ve observed about gabapentin’s side effects in my practice …
Physical Adverse Effects
I’ve seen patients become lethargic or develop vomiting, diarrhea and tremors. These adverse effects all went away when we stopped the drug.
Two elderly patients developed signs of cognitive disorder. They experienced head pressing, got stuck in corners, and would stare into space. Both of them recovered after stopping the drug.
Rita Hogan, a canine herbalist, shared her experiences with me about gabapentin for dogs. She reported dogs becoming more aggressive and exhibiting signs of dementia and memory loss. Rita also saw a family member develop signs of senility, memory loss, and confusion with this drug.
Lack Of Efficacy In Gabapentin Pain Management
I haven’t seen a case where gabapentin really made a difference in pain management. So why exactly is the veterinary community prescribing this drug, which …
- Has caused deleterious side effects in humans
- Was part of the largest pharmaceutical fraud settlements in history
- Has no FDA approval for the conditions it’s used to treat
- Hasn’t been effective in any double-blind placebo-controlled trials
- May actually prevent the nervous system from repairing itself
But there are other things you can give your dog to bring him pain relief without changing his personality or creating a constant state of listlessness.
Safe Alternatives To Gabapentin For Dogs
When I get dogs off of gabapentin, I use many different natural options for pain management. They’re much safer and more effective alternatives to gabapentin … a drug that has NO scientific evidence or FDA approval to back it up.
Some of the best options for pain management in dogs are:
- Electroacupuncture (specifically for nerve pain)
- Chinese herbs
- Western herbs
- Homeopathic remedies
Ever since I finished vet school there’s been extraordinary pressure on holistic practitioners. There’s a demand to provide “double-blind, placebo-controlled studies” to prove that alternative options work. Yet Big Pharma can release drugs prescribed for off-label use without any studies. Not even safety studies! And for drugs that have severe, sometimes life-threatening side effects.
And, as we saw with gabapentin … when they can’t use them on the human market, they unload them on veterinarians. This veterinarian isn’t taking the bait!
Enke O, MBBS MSc et al. Anticonvulsants in the treatment of low back pain and lumbar radicular pain: a systematic review and meta-analysis. CMAJ. 2018 Jul 3; 190(26): E786–E793.
Eroglu C et al. Gabapentin receptor alpha2delta-1 is a neuronal thrombospondin receptor responsible for excitatory CNS synaptogenesis. Cell. 2009 Oct 16;139(2):380-92.